SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '54c1a35ad4856978ddaf36058a151ceef39e91bbbf6f32ffe91557ad3cb99bcb' 
  AND token = 'I3ugNwj75vbTzM0vk0RHPciGcmrmMyHtVbkuo5bnug0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}